Scientists regarded as Neo Lamarckists are

The correct option is Kammerer and Mc Dougall.

Understanding Lamarckism and Neo-Lamarckism:
Lamarckism, proposed by Jean-Baptiste Lamarck, is the theory of evolution based on the inheritance of acquired characteristics. It suggests that physical modifications acquired by an organism during its lifetime in response to environmental influences are directly transmitted to its offspring.
Neo-Lamarckism is a modified version of this theory that emerged in the late 19th and early 20th centuries. Neo-Lamarckists sought to adapt Lamarck's original ideas to fit new biological discoveries, proposing that environmental factors can directly or indirectly affect the germ cells (germplasm) of an organism, thereby causing the acquired variations to become heritable.

Role of the Correct Scientists:
1. Paul Kammerer: An Austrian biologist who performed experiments on amphibians, such as midwife toads and salamanders, attempting to show that acquired adaptations (like developing nuptial pads or changing skin color patterns due to altered environments) could be inherited by the next generation.
2. William McDougall: A psychologist and biologist who conducted experiments on rats over many generations, training them to escape from a water tank. He observed that successive generations required fewer trials to learn the task, which he interpreted as the inheritance of acquired learning.

Why the Other Options Are Incorrect:
• Correns, Hugo de Vries and Tschermak: These three botanists are famous for independently rediscovering Gregor Mendel's laws of inheritance in 1900. Hugo de Vries is also known for proposing the Mutation Theory of evolution.
• August Weismann and T.H Morgan: August Weismann formulated the Germ Plasm Theory, which actively opposed Lamarckism by demonstrating that changes in somatic cells (body cells) do not affect germ cells and cannot be inherited. Thomas Hunt Morgan established the chromosome theory of heredity using fruit flies (Drosophila).
• Hardy Weinberg: G.H. Hardy and Wilhelm Weinberg formulated the Hardy-Weinberg principle, which is a mathematical model describing genetic equilibrium in populations under Mendelian inheritance, not Lamarckian evolution.